Separated medium environments for communication and broadcasting are now being integrated at high speed thanks to the development of information communication technology including a network of multimedia contents and the digitalization and the broadband trend of the network.
As each service provider can easily provide a supplementary service beyond the existing specific service area, border between communication and broadcasting becomes vague, thereby speeding the integration of communication and broadcasting. Such service is referred to as a communication-broadcast integrated service. That is, a communication service provider has pursued the offer of the integrated service in order to provide multimedia contents having higher value added, while a broadcast service provider has made an effort to provide a communication service through a broadcast network and an interactive service overcoming the limitation of conventional uni-directional broadcasting services.
Such a communication-broadcast integrated service may be largely classified into three types of services. A first type of service is a broadcasting service through a communication network such as an Internet broadcasting service, a video on demand (VOD)/music on demand (MOD) service and an electric light board broadcasting service. A second type of service is a communication service through a broadcasting network such as an ultra high speed Internet access service using a cable TV network and an FM paging service using a frequency modulation network and a supplementary service. A third type of service is an integrated service of a communication network and a broadcasting network such as an interactive data broadcasting service, an electronic commerce, a web browsing and a mail service.
In particular, mobile communication and broadcasting has been rapidly integrated according to the bandwidth expansion of a mobile communication network and the development of information communication technology. The integrated service of the mobile communication and the broadcasting may be largely classified into a mobile communication broadcasting service providing a broadcasting function through a mobile communication network and an interactive data broadcasting service using mobile communication.
FIG. 1 is a diagram showing an integrated service according to the integration of mobile communication and a broadcasting service.
According to the wide spread of digital cameras and multifunctional terminals having camcorder functions and the requirement of mobile communication subscribers intended for exchange of music, images, animations, moving pictures, etc., a mobile communication broadcasting service has been developed from a single sentence-centered short message service (hereinafter, referred to as SMS) to a multimedia message service (hereinafter, referred to as MMS). However, in the SMS and the MMS, since data are transmitted between a base station and a terminal by means of a point-to-point scheme, it is difficult to introduce a broadcast concept. In order to improve such a disadvantage, a cell broadcast short message service (hereinafter, referred to as CBS) capable of transmitting the SMS by means of a point-to-multipoint scheme has been developed. Therefore, a broadcast concept has been introduced.
Currently, domestic mobile communication carriers have provided a CBS using a 3rd generation partnership project (hereinafter, referred to as GPP) scheme capable of supporting contents of images, voice, or moving pictures of 180 Bytes at maximum. A CBS using a 3GPP2 scheme can support a data transmission speed of 1.23 Kbytes at maximum. However, recently, such a low speed of CBS experiences limitation in providing multimedia application programs. In order to improve such a disadvantage, a trial to provide a broadcasting service of 256 Kbps through an asynchronous multimedia broadcast multicast service (hereinafter, referred to as MBMS) technology and a synchronous BCMCS technology, which use broadcast dedicated channels, has been performed in the 3G mobile communication network.
First, the MBMS is a high speed data broadcasting service in which a plurality of user equipments (hereinafter, referred to as UE) can simultaneously receive data after the data have been transmitted one time. In the MBMS, the 3GPP classifies and defines a broadcast mode and a multicast mode. In the broadcast mode, all subscribers located in a service coverage can be receive a multimedia service, which includes texts, voice, pictures, images, etc., according to setting regarding whether to receive broadcast data through setting of a equipment without a complicated service subscription procedure. In contrast, in the multicast mode, only specific subscribers having joined a corresponding service can receive the service. Therefore, most services are provided with a fee.
Meanwhile, the BCMCS is a service for which standardization is in progress by the 3rd GPP2 which is a synchronous researcher group. In the BCMCS, a multimedia service, which includes streaming, texts, pictures, images, etc., is provided to a plurality of users through one link. To provide the multimedia service, a system assigns separate channels or slots for broadcast/multicast and enables many subscribers to simultaneously receive multicast contents.
Further, with the increase of multimedia users and the requirement for a ubiquitous service, the standardization for the BCMCS is in progress in such a manner that the BCMCS is differentiated from the broadcasting service of a satellite digital multimedia broadcasting (DMB) and relates to the conventional multimedia broadcasting service through an high-degree development of a CDMA 2000 1xEV-DO (hereinafter, referred to as 1xEV-DO) network. In particular, a domestic carrier (e.g., SK telecom, KTF, etc) having constructed the 1xEV-DO network, Hitachi and KDDA in Japan, Samsung electronics, Qualcomm Incorporated, etc., insist the necessity of the BCMCS and have actively joined in establishing the standard for the BCMCS.
FIG. 2 is a table showing progress status according to each working group regarding a standardization work for the BCMCS in the 1xEV-DO network.
To provide the BCMCS in the 1xEV-DO network, a service provider appoints an FA through which the BCMCS will be provided and provide the BCMCS through the appointed frequency. However, enormous cost of more than 100 billion won is required for installing one frequency resource. Accordingly, it is preferred to utilize an unused frequency resource of the existing frequency resource. However, since each mobile communication carrier currently does not almost have the unused frequency resource, it is very difficult to efficiently provide the BCMCS.